Before the convention even began Monday morning, Trump supporters were lining up to bash Republicans who had not endorsed the presumptive nominee, especially the Bush family.
Donald Trump's campaign chairman, Paul Manafort, started the day by saying the Bushes are "part of the past."
"Certainly the Bush family, while we would have liked to have had them, they're part of the past," Manafort said at a morning briefing. "We're dealing with the future."
He said Republican voters who nominated Trump are moving ahead with or without the Bushes and other naysayers.
"They do not reflect the broad strokes of the Republican Party," he said. "We hope that when the Bush family decides to participate again in the political process, they will join us. But healing takes time, and we understand that."
In an opinion piece for the Washington Post over the weekend, Jeb Bush made clear he won't be supporting Trump for president, "While he has no doubt tapped into the anxiety so prevalent in the United States today, I do not believe Donald Trump reflects the principles or inclusive legacy of the Republican Party. And I sincerely hope he doesn't represent its future.
"I haven't decided how I'll vote in November — whether I'll support the Libertarian ticket or write in a candidate — but I do know there are a lot of things Republicans can do in the coming months to lay the groundwork for rebuilding our party and the foundation for a true conservative renewal in our country," Bush wrote.
His brother, former President George W. Bush, and his father, former President George Bush, also announced in May that they would not be endorsing a presidential candidate this time around. It's also unusual that both of the former presidents are remaining on the sidelines and will not be part of their party's convention this week.
Newt Gingrich says the Bush family is behaving "childishly" for skipping this week's gathering in Cleveland.
In a Monday morning interview with ABC's Good Morning America, the former GOP House speaker said "the Republican Party has been awfully good to the Bushes and they're showing remarkably little gratitude."
He said the family needs to "get over" former Florida Gov. Jeb Bush's loss to Donald Trump in the primary.
Gov. Chris Christie of New Jersey also told a group of Michigan delegates on Monday it's unacceptable that leading Republicans are not endorsing Trump.
Christie recalled that he and the other GOP presidential candidates pledged to support the eventual nominee.
"It is unacceptable to me and it should be unacceptable to you that anyone who signed that pledge is not now adhering to that pledge and supporting our party's nominee," said Christie, who didn't call anyone out by name.
Of course, one of those names would have to be Jeb Bush, who once pledged to support the eventual nominee but he is not supporting Trump.
Christie added: "Everyone has a right to their own conscience and their own beliefs. But the fact of the matter is as I said before, if you're a Republican and you have voted for Republican nominees for president and you're not working for Donald Trump, you're working for Hillary. And that's the bottom line."
Information from the Los Angeles Times, Associated Press and Washington Post was used in this report.